Excel Tips

A few different websites for Tips on Excel
http://www.vertex42.com/ExcelLinks/cat/excel-tips-tricks-1.html
http://spreadsheets.about.com/od/tipsandfaqs/a/excel_tip_hub.htm
http://office.microsoft.com/en-us/help/six-great-tips-from-this-isnt-excel-its-magic-by-bob-umlas-HA010282444.aspx